A wildfire that's scorched more than 480 square miles in the Okefenokee Swamp is still burning deep underground after nearly eight months, though officials said it's barely growing.

Rangers with the Okefenokee National Wildlife Refuge said the fire has burned a total of 309,200 acres in southeast Georgia near the Florida state line, growth of just one acre since October.

Still, officials said dead and decaying vegetation continues to burn deep underground on the refuge's west side, producing smoke but no visible flame. And after months of drought there's still not enough water in the swamp to snuff the fire for good.

Twelve people remain assigned to the firefighting crew in charge of monitoring the wildfire.